Compositions which include 1,1,2,2- tetrafluoroethane and fluoroethane

ABSTRACT

Compositions are disclosed which include 1,1,2,2-tetrafluoroethane and a propane, tris(trifluoromethyl)amine, trifluoromethylsulfur pentafluoride or fluoroethane. The term propane includes compounds of the formula C3FaH8-a wherein 0&lt;/=a&lt;/=8 as well as cyclic compounds of the formula C3FbH6-b wherein 0&lt;/=b&lt;/=6. These compositions are useful as refrigerants, cleaning agents, expansion agents for polyolefins and polyurethanes, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, power cycle working fluids, polymerization media, particulate removal fluids, carrier fluids, buffing abrasive agents, and displacement drying agents.

CROSS-REFERENCE TO EARLIER FILED APPLICATIONS

This is a division of Ser. No. 08/748,119, filed on Nov. 12, 1996,allowed, which is a continuation-in-part of application Ser. No.08/192,908, filed Feb. 7, 1994, abandoned, which is acontinuation-in-part of application Ser. No. 08/089,004, filed Jul. 9,1993, abandoned, which is a continuation-in-part of application Ser. No.07/913,642, filed Jul. 15, 1992, abandoned.

FIELD OF THE INVENTION

This invention relates to compositions that include1,1,2,2-tetrafluoroethane as a component. These compositions are usefulas refrigerants, cleaning agents, expansion agents for polyolefins andpolyurethanes, aerosol propellants, refrigerants, heat transfer media,gaseous dielectrics, fire extinguishing agents, power cycle workingfluids, polymerization media, particulate removal fluids, carrierfluids, buffing abrasive agents, and displacement drying agents.

BACKGROUND OF THE INVENTION

Fluorinated hydrocarbons have many uses, one of which is as arefrigerant. Such refrigerants include dichlorodifluoromethane (CFC-12)and chlorodifluoromethane (HCFC-22).

In recent years it has been pointed out that certain kinds offluorinated hydrocarbon refrigerants released into the atmosphere mayadversely affect the stratospheric ozone layer. Although thisproposition has not yet been completely established, there is a movementtoward the control of the use and the production of certainchlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) under aninternational agreement.

Accordingly, there is a demand for the development of refrigerants thathave a lower ozone depletion potential than existing refrigerants whilestill achieving an acceptable performance in refrigeration applications.Hydrofluorocarbons (HFCs) have been suggested as replacements for CFCsand HCFCs since HFCs have no chlorine and therefore have zero ozonedepletion potential.

In refrigeration applications, a refrigerant is often lost duringoperation through leaks and shaft seals, hose connections, solderedjoints and broken lines. In addition, the refrigerant may be released tothe atmosphere during maintenance procedures on refrigeration equipment.If the refrigerant is not a pure component or an azeotrope orazeotrope-like composition, the refrigerant composition may change whenleaked or discharged to the atmosphere from the refrigeration equipment,causing the refrigerant to become flammable or to have poorrefrigeration performance.

Accordingly, it is desirable to use as a refrigerant a pure compound oran azeotropic or azeotrope-like composition that includes two or morecompounds.

Fluorinated hydrocarbons may also be used as a cleaning agent or solventto clean, for example, electronic circuit boards. It is desirable thatthe cleaning agents be azeotropic or azeotrope-like because in vapordegreasing operations the cleaning agent is generally redistilled andreused for final rinse cleaning.

Azeotropic or azeotrope-like compositions that include a fluorinatedhydrocarbon are also useful as blowing agents in the manufacture ofclosed-cell polyurethane, phenolic and thermoplastic foams, aspropellants in aerosols, as heat transfer media, gaseous dielectrics,fire extinguishing agents, power cycle working fluids, such as for heatpumps, inert media for polymerization reactions, fluids for removingparticulates from metal surfaces, as carrier fluids that may be used,for example, to place a fine film of lubricant on metal parts, or asbuffing abrasive agents to remove buffing abrasive compounds frompolysurfaces such as metal, as displacement drying agents for removingwater, such as from jewelry or metal parts, as resist developers inconventional circuit manufacturing techniques including chlorine-typedeveloping agents, and as strippers for photoresists when used with, forexample, a chlorohydrocarbon, such as 1,1,1 -trichloroethane ortrichloroethylene.

SUMMARY OF THE INVENTION

The present invention relates to the discovery of compositions of1,1,2,2-tetrafluoroethane and a propane, tris(trifluoromethyl)amnine,trifluoromethylsulfur pentafluoride or fluoroethane. As used herein, theterm propane includes compounds of the formula C₃ F_(a) H_(8-a) wherein0≦a≦8 as well as cyclic compounds of the formula C₃ F_(b) H_(6-b)wherein 0≦b≦6. These compositions are useful as refrigerants, cleaningagents, expansion agents for polyolefins and polyurethanes, aerosolpropellants, heat transfer media, gaseous dielectrics, fireextinguishing agents, power cycle working fluids, polymerization media,particulate removal fluids, carrier fluids, buffing abrasive agents, anddisplacement drying agents. Further, the invention relates to thediscovery of binary azeotropic or azeotrope-like compositions comprisingeffective amounts of 1,1,2,2-tetrafluoroethane and a fluorinatedpropane, tris(trifluoromethyl)amine, trifluoromethylsulfur pentafluorideor fluoroethane to form an azeotropic or azeotrope-like composition.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph of the vapor pressure of liquid mixtures of HFC-134and HFC-227ca at 11.2'C;

FIG. 2 is a graph of the vapor pressure of liquid mixtures of HFC-134and HFC-245cb at 11.2'C;

FIG. 3 is a graph of the vapor pressure of liquid mixtures of HFC-134and (CF₃)₃ N at 25'C;

FIG. 4 is a graph of the vapor pressure of liquid mixtures of HFC-134and SF₅ CF₃ at 14.4'C;

FIG. 5 is a graph of the vapor pressure of liquid mixtures of HFC-134and cyclopropane at 43.9'C;

FIG. 6 is a graph of the vapor pressure of liquid mixtures of HFC-134and C216 at 25'C;

FIG. 7 is a graph of the vapor pressure of liquid mixtures of HFC-134and HFC-263fb at 25'C;

FIG. 8 is a graph of the vapor pressure of liquid mixtures of HFC-134and HFC-272ca at 25'C;

FIG. 9 is a graph of the vapor pressure of liquid mixtures of HFC-134and HFC-281ea at 25'C; and

FIG. 10 is a graph of the vapor pressure of liquid mixtures of HFC-134and HFC-281fa at 25'C.

DETAILED DESCRIPTION

The present invention relates to compositions of1,1,2,2-tetrafluoroethane (HFC-134), boiling point=-19.7'C and apropane, tris(trifluoromethyl)amine, trifluoromethylsulfur pentafluorideor fluoroethane. As used herein, the term propane includes compounds ofthe formula C₃ F_(a) H_(8-a) wherein 0≦a≦8 as well as cyclic compoundsof the formula C₃ F_(b) H_(6-b) wherein 0≦b≦6. Compounds of the formulaC₃ F_(a) H_(8-a) wherein 0≦a≦8 include 1,1,1,2,2,3,3-heptafluoropropane(HFC-227ca, or CHF₂ CF₂ CF₃, boiling point=-17.0'C),1,1,1,2,2-pentafluoropropane (HFC-245cb or CF₃ CF₂ CH₃, boilingpoint=-17.5'C), boiling point=-31.5'C), 1,1,1-trifluoropropane(HFC-263fb, or CH₃ CH₂ CF₃, boiling point=-13.0'C), 2,2-difluoropropane(HFC-272ca, or CH₃ CF₂ CH₃, boiling point=-0.4'C), 2-fluoropropane(HFC-281ea, or CH₃ CHFCH₃, boiling point=-9.4'C) and 1-fluoropropane(HFC-281fa, or CH₃ CH₂ CH₂ F, boiling point=-2.5'C). Cyclic compounds ofthe formula C₃ F_(b) H_(6-b) wherein 0≦b≦6 include cyclopropane (C₃ H₆(cyclic), boiling point=-32.8'C), perfluorocyclopropane (C216, or CF₂CF₂ CF₂ (cyclic).

HFC-227ca (CAS Reg. No. 2252-84-8) has been prepared by reaction of2,2,3,3-tetrafluoropropionic acid with SF₄ in the presence of borontrifluoride as reported by Hasek, et. al. in J. Am. Chem. Soc., Vol. 82,pp. 543-551 (1960).

HFC-245cb (CAS Reg. No. 1814-88-6) can be made by reaction of methylchloride and cesium fluoride with tetrafluoroethylene in triethyleneglycol dimethyl ether as disclosed by Yale in U.S. Pat. No. 3,381,042.

C216 (CAS Reg. No. 931-91-9) has been made by photolysis oftetrafluoroethylene in the presence of ethylene diluent as disclosed byMastrangelo in U.S. Pat. No. 3,228,864.

HFC-263fb (CAS Reg. No. 421-07-8) has been prepared by reaction of 1,1-dichloropropene with HF at 90-100 C. as reported by McBee, et. al. inJ. Am. Chem. Soc., Vol. 69, pp. 944-947 (1947).

HFC-272ca (CAS Reg. No. 420-45-1) has been made by fluorination of2,2-dichloropropane with SbF3 as reported by Henne and Renoll in J. Am.Chem. Soc., Vol. 59, pp. 2434-2436 (1937).

Tris(trifluoromethyl)amine (CF₃)₃ N, boiling point=-6.5'C), (CAS Reg.No. 432-03-1) has been made by electrochemical fluorination of trimethylamine in anhydrous hydrogen fluoride as disclosed by Kauck and Simons inU.S. Pat. No. 2,616,927.

Trifluoromethylsulfur pentafluoride (SF₅ CF₃, boiling point=-20.4'C),(CAS Reg. No. 373-80-8) has been made by electrochemical fluorination ofthiourea as reported by Schmeisser and Huber in Z. Naturforsch., Sect.B, Vol. 21, pp. 285-286 (1966).

Fluoroethane (HFC-161, or CH₃ CFH₂, boiling point=-37.7'C), (CAS Reg.No. 353-36-6), HFC-281ea (isopropyl fluoride, CAS Reg. No. 420-26-8),and HFC-281fa (n-propyl fluoride, CAS Reg. No. 460-13-9) have beenprepared by reaction of hydrogen fluoride with ethylene, propylene, andcyclopropane, respectively, as reported by Grosse and Lin in J. Org.Chem., Vol. 3, pp. 26-32 (1938).

The following compositions can be used as refrigerants.

                  TABLE 1                                                         ______________________________________                                        Composition No.                                                               ______________________________________                                        1          1-99 wt % HFC-134                                                                           1-99 wt % HFC-227ca                                  2          1-99 wt % HFC-134                                                                           1-99 wt % HFC-245cb                                  3          1-99 wt % HFC-134                                                                           1-99 wt % (CF.sub.3).sub.3 N                         4          1-99 wt % HFC-134                                                                           1-99 wt % SF.sub.5 CF.sub.3                          5          1-99 wt % HFC-134                                                                           1-99 wt % cyclopropane                               6          1-99 wt % HFC-134                                                                           1-99 wt % C216                                       7          1-99 wt % HFC-134                                                                           1-99 wt % HFC-161                                    8          1-99 wt % HFC-134                                                                           1-99 wt % HFC-263fb                                  9          1-99 wt % HFC-134                                                                           1-99 wt % HFC-272ca                                  10         1-99 wt % HFC-134                                                                           1-99 wt % HFC-281ea                                  11         1-99 wt % HFC-134                                                                           1-99 wt % HFC-281fa                                  ______________________________________                                    

The present invention also relates to the discovery of azeotropic orazeotrope-like compositions of effective amounts of HFC-134 and a secondcomponent to form an azeotropic or azeotrope-like composition, whereinthe second component is HFC-227ca, HFC-245cb, (CF₃)₃ N, SF₅ CF₃,cyclopropane, C216, HFC-161, HFC-263fb, HFC-272ca, HFC-281ea orHFC-281fa.

By "azeotropic" composition is meant a constant boiling liquid admixtureof two or more substances that behaves as a single substance. One way tocharacterize an azeotropic composition is that the vapor produced bypartial evaporation or distillation of the liquid has the samecomposition as the liquid from which it was evaporated or distilled,that is, the admixture distills/refluxes without compositional change.Constant boiling compositions are characterized as azeotropic becausethey exhibit either a maximum or minimum boiling point, as compared withthat of the non-azeotropic mixtures of the same components.

By "azeotrope-like" composition is meant a constant boiling, orsubstantially constant boiling, liquid admixture of two or moresubstances that behaves as a single substance. One way to characterizean azeotrope-like composition is that the vapor produced by partialevaporation or distillation of the liquid has substantially the samecomposition as the liquid from which it was evaporated or distilled,that is, the admixture distills/refluxes without substantial compositionchange. Another way to characterize an azeotrope-like composition isthat the bubble point vapor pressure and the dew point vapor pressure ofthe composition at a particular temperature are substantially the same.

It is recognized in the art that a composition is azeotrope-like if,after 50 weight percent of the composition is removed such as byevaporation or boiling off, the difference in vapor pressure between theoriginal composition and the composition remaining after 50 weightpercent of the original composition has been removed is less than 10percent, when measured in absolute units. By absolute units, it is meantmeasurements of pressure and, for example, psia, atmospheres, bars,torr, dynes per square centimeter, millimeters of mercury, inches ofwater and other equivalent terms well known in the art. If an azeotropeis present, there is no difference in vapor pressure between theoriginal composition and the composition remaining after 50 weightpercent of the original composition has been removed.

Therefore, included in this invention are compositions of effectiveamounts of HFC-134 and a second component, wherein the second componentis HFC-227ca, HFC-245cb, (CF₃)₃ N, SF₅ CF₃, cyclopropane, C216, HFC-161,HFC-263fb, HFC-272ca, HFC-281ea or HFC-281fa such that after 50 weightpercent of an original composition is evaporated or boiled off toproduce a remaining composition, the difference in the vapor pressurebetween the original composition and the remaining composition is 10percent or less.

Substantially constant boiling, azeotropic or azeotrope-likecompositions of this invention comprise the following (all compositionsare measured at 25'C):

1. 1-99, preferably 40-90, most preferably 61.1 wt % HFC-134; 1-99,preferably 10-60, most preferably 38.9 wt % HFC-227ca.

2. 1-99, preferably 30-90, most preferably 60.4 wt % HFC-134; 1-99,preferably 10-70, most preferably 39.6 wt % HFC-245cb.

3. 27-84, preferably 40-70, most preferably 56.4 wt % HFC-134; 16-73,preferably 30-60, most preferably 43.6 wt % (CF₃)₃ N.

4. 1-71, preferably 20-71, most preferably, 37.8 wt % HFC-134; 29-99,preferably 29-80, most preferably 62.2 wt % SF₅ CF₃.

5. 1-84, preferably 40-84, most preferably 50.5 wt % HFC-134; 16-99,preferably 16-60, most preferably 49.5 wt % cyclopropane.

6. 1-99, preferably 10-50, most preferably 29.2 wt % HFC-134; 1-99,preferably 50-90, most preferably 70.8 wt % FC-C216.

7. 1-99, preferably 50-99 wt % HFC-134; 1-99, preferably 1-50 wt %HFC-161.

8. 31-99, preferably 50-99, most preferably 67.2 wt % HFC-134; 1-69,preferably 1-50, most preferably 32.8 wt % HFC-263fb.

9. 51-99, preferably 70-99, most preferably 84.0 wt % HFC-134; 1-49,preferably 1-30, most preferably 16.0 wt % HFC-272ca.

10. 48-99, preferably 70-99, most preferably 84.7 wt % HFC-134; 1-52,preferably 1-30, most preferably 15.3 wt % HFC-281ea.

11. 58-99, preferably 80-99, most preferably 93.8 wt % HFC-134; 1-42,preferably 1-20, most preferably 6.2 wt % HFC-281fa.

The components of the compositions of this invention have the followingvapor pressures at 25'C.

    ______________________________________                                        COMPONENTS         PSIA   KPA                                                 ______________________________________                                        HFC-134            76.1   525                                                 HFC-227ca          63.8   440                                                 HFC-245cb          67.4   465                                                 (CF.sub.3).sub.3 N 45.8   316                                                 SF.sub.5 CF.sub.3  74.7   515                                                 Cyclopropane       105.0  724                                                 C216               95.1   655                                                 HFC-161            130.2  898                                                 HFC-263fb          54.0   372                                                 HFC-272ca          34.5   238                                                 HFC-281ea          47.1   325                                                 HFC-281fa          37.7   260                                                 ______________________________________                                    

For purposes of this invention, "effective amount" is defined as theamount of each component of the inventive compositions which, whencombined, results in the formation of an azeotropic or azeotrope-likecomposition. This definition includes the amounts of each component,which amounts may vary depending on the pressure applied to thecomposition so long as the azeotropic or azeotrope-like compositionscontinue to exist at the different pressures, but with possibledifferent boiling points.

Therefore, effective amount includes the amounts, such as may beexpressed in weight percentages, of each component of the compositionsof the instant invention which form azeotropic or azeotrope-likecompositions at temperatures or pressures other than as describedherein.

For the purposes of this discussion, azeotropic or constant-boiling isintended to mean also essentially azeotropic or essentially-constantboiling. In other words, included within the meaning of these terms arenot only the true azeotropes described above, but also othercompositions containing the same components in different proportions,which are true azeotropes at other temperatures and pressures, as wellas those equivalent compositions which are part of the same azeotropicsystem and are azeotrope-like in their properties. As is well recognizedin this art, there is a range of compositions which contain the samecomponents as the azeotrope, which will not only exhibit essentiallyequivalent properties for refrigeration and other applications, butwhich will also exhibit essentially equivalent properties to the trueazeotropic composition in terms of constant boiling characteristics ortendency not to segregate or fractionate on boiling.

It is possible to characterize, in effect, a constant boiling admixturewhich may appear under many guises, depending upon the conditionschosen, by any of several criteria:

* The composition can be defined as an azeotrope of A, B, C (and D . . .) since the very term "azeotrope" is at once both definitive andlimitative, and requires that effective amounts of A, B, C (and D . . .) for this unique composition of matter which is a constant boilingcomposition.

* It is well known by those skilled in the art, that, at differentpressures, the composition of a given azeotrope will vary at least tosome degree, and changes in pressure will also change, at least to somedegree, the boiling point temperature. Thus, and azeotrope of A, B, C(and D . . . ) represents a unique type of relationship but with avariable composition which depends on temperature and/or pressure.Therefore, compositional ranges, rather than fixed compositions, areoften used to define azeotropes.

* The composition can be defined as a particular weight percentrelationship or mole percent relationship of A, B, C (and D . . . ),while recognizing that such specific values point out only oneparticular relationship and that in actuality, a series of suchrelationships, represented by A, B, C (and D . . . ) actually exist fora given azeotrope, varied by the influence of pressure.

* An azeotrope of A, B, C (and D . . . ) can be characterized bydefining the compositions as an azeotrope characterized by a boilingpoint at a given pressure, thus giving identifying characteristicswithout unduly limiting the scope of the invention by a specificnumerical composition, which is limited by and is only as accurate asthe analytical equipment available.

The azeotrope or azeotrope-like compositions of the present inventioncan be prepared by any convenient method including mixing or combiningthe desired amounts. A preferred method is to weigh the desiredcomponent amounts and thereafter combine them in an appropriatecontainer.

For compositions that are azeotropic, there is usually some range ofcompositions around the azeotrope that, for a maximum boiling azeotrope,have boiling points at a particular pressure higher than the purecomponents of the composition at that pressure and have vapor pressureslower at a particular temperature than the pure components of thecomposition at that temperature, and that, for a minimum boilingazeotrope, have boiling points at a particular pressure lower than thepure components of the composition at that pressure and have vaporpressures higher at a particular temperature than the pure components ofthe composition at that temperature. Boiling temperatures and vaporpressures above or below that of the pure components are caused byunexpected intermolecular forces between and among the molecules of thecompositions, which can be a combination of repulsive and attractiveforces such as van der Waals forces and hydrogen bonding.

The range of compositions that have a maximum or minimum boiling pointat a particular pressure, or a maximum or minimum vapor pressure at aparticular temperature, may or may not be coextensive with the range ofcompositions that are substantially constant boiling. In those caseswhere the range of compositions that have maximum or minimum boilingtemperatures at a particular pressure, or maximum or minimum vaporpressures at a particular temperature, are broader than the range ofcompositions that are substantially constant boiling according to thechange in vapor pressure of the composition when 50 weight percent isevaporated, the unexpected intermolecular forces are nonethelessbelieved important in that the refrigerant compositions having thoseforces that are not substantially constant boiling may exhibitunexpected increases in the capacity or efficiency versus the componentsof the refrigerant composition.

Specific examples illustrating the invention are given below. Unlessotherwise stated therein, all percentages are by weight. It is to beunderstood that these examples are merely illustrative and in no way areto be interpreted as limiting the scope of the invention.

EXAMPLE 1 Phase Study

A phase study on the following compositions, wherein the composition isvaried and the vapor pressures is measured, at a constant temperature of25'C, shows that the following compositions are azeotropic.

    ______________________________________                                        Com-                                                                          position            Vapor Press.                                              No.                                psia (kpa)                                 ______________________________________                                        1     61.1 wt % HFC-34                                                                            38.9 wt % HFC-227ca                                                                           80.4 (554)                                2     60.4 wt % HFC-34                                                                            39.6 wt % HFC-245cb                                                                           81.2 (560)                                3     56.4 wt % HFC-134                                                                           43.6 wt % (CF.sub.3).sub.3 N                                                                  92.3 (636)                                4     37.8 wt % HFC-134                                                                           62.2 wt % SF.sub.5 CF.sub.3                                                                  106.2 (732)                                5     50.5 wt % HFC-134                                                                           49.5 wt % cyclopropane                                                                       123.0 (848)                                6     29.2 wt % HFC-134                                                                           70.8 wt % C216 103.9 (716)                                8     67.2 wt % HFC-134                                                                           32.8 wt % HFC-263fb                                                                           87.3 (602)                                9     84.0 wt % HFC-134                                                                           16.0 wt % HFC-272ca                                                                           80.3 (554)                                10    84.7 wt % HFC-134                                                                           15.3 wt % HFC-281ea                                                                           81.6 (563)                                11    93.8 wt % HFC-134                                                                            6.2 wt % HFC-281fa                                                                           76.9 (530)                                ______________________________________                                    

EXAMPLE 2 Impact of Vapor Leakage on Vapor Pressure at 25'C

A vessel is charged with an initial composition at 25'C, and the vaporpressure of the composition is measured. The composition is allowed toleak from the vessel, while the temperature is held constant at 25'C,until 50 weight percent of the initial composition has been removed, atwhich time the vapor pressure of the composition remaining in the vesselis measured. The results are summarized below.

    ______________________________________                                                                            0%                                                                  50 wt %   change                                    Refrigerant  0 wt % evaporated                                                                          evaporated                                                                              in vapor                                  Composition  psia (kPa)   psia (kPa)                                                                              pressure                                  ______________________________________                                        HFC-134/HFC-227ca                                                             99.0/1.0      76.3 (526)   76.3 (526)                                                                             0.0                                       80.0/20.0     79.4 (547)   79.2 (546)                                                                             0.3                                       61.1/38.9     80.4 (554)   80.4 (554)                                                                             0.0                                       40.0/60.0     79.1 (545)   78.6 (542)                                                                             0.6                                       20.0/80.0     74.6 (514)   72.9 (503)                                                                             2.3                                       10.0/90.0     70.3 (485)   68.5 (472)                                                                             2.6                                        1.0/99.0     64.6 (445)   64.3 (443)                                                                             0.5                                       HFC-134/HFC-245cb                                                             99.0/1.0      76.4 (527)   76.3 (526)                                                                             0.1                                       90.0/10.0     78.6 (542)   78.1 (538)                                                                             0.6                                       80.0/20.0     80.1 (552)   79.8 (550)                                                                             0.4                                       60.4/39.6     81.2 (560)   81.2 (560)                                                                             0.0                                       40.0/60.0     80.0 (552)   79.6 (549)                                                                             0.5                                       20.0/80.0     76.0 (524)   74.6 (514)                                                                             1.8                                       10.0/90.0     72.4 (499)   71.1 (490)                                                                             1.8                                        1.0/99.0     68.0 (469)   67.8 (467)                                                                             0.3                                       HFC-134/(CF.sub.3).sub.3 N                                                    84.0/16.0     89.5 (617)   80.7 (557)                                                                             9.8                                       70.0/30.0     91.8 (633)   90.5 (624)                                                                             1.4                                       56.4/43.6     92.3 (636)   92.3 (636)                                                                             0                                         40.0/60.0     91.3 (629)   89.5 (617)                                                                             2.0                                       27.0/73.0     88.1 (607)   79.6 (549)                                                                             9.6                                       HFC-134/SF.sub.5 CF.sub.3                                                     72.0/28.0    100.9 (696)   90.5 (624)                                                                             10.3                                      71.0/29.0    101.2 (698)   91.5 (631)                                                                             9.6                                       60.0/40.0    104.0 (717)  100.5 (693)                                                                             3.4                                       37.8/62.2    106.2 (732)  106.2 (732)                                                                             0.0                                       20.0/80.0    103.4 (713)  100.7 (694)                                                                             2.6                                       10.0/90.0     96.9 (668)   91.4 (630)                                                                             5.7                                        1.0/99.0     83.4 (575)   82.0 (565)                                                                             1.7                                       HFC-134/cyclopropane                                                          50.5/49.5    123.0 (848)  123.0 (848)                                                                             0.0                                       70.0/30.0    120.4 (830)  117.3 (809)                                                                             2.6                                       80.0/20.0    115.4 (796)  106.9 (737)                                                                             7.4                                       85.0/15.0    110.8 (764)   99.1 (683)                                                                             10.6                                      84.0/16.0    111.8 (771)  100.8 (695)                                                                             9.8                                       30.0/70.0    121.0 (834)  118.4 (816)                                                                             2.1                                       10.0/90.0    113.5 (783)  107.9 (744)                                                                             4.9                                        1.0/99.0    106.1 (732)  105.2 (725)                                                                             0.8                                       HFC-134/C216                                                                  99.0/1.0      77.1 (532)   76.4 (527)                                                                             0.9                                       50.0/50.0    101.7 (701)  100.3 (692)                                                                             1.4                                       29.2/70.8    103.9 (716)  103.9 (716)                                                                             0                                         10.0/90.0    100.8 (695)  100.0 (689)                                                                             0.8                                        1.0/99.0     95.8 (661)   95.6 (659)                                                                             0.2                                       HFC-134/HFC-161                                                                1.0/99.0    130.3. (898) 130.3 (898)                                                                             0.0                                       10.0/90.0    130.0 (896)  129.9 (896)                                                                             0.1                                       20.0/80.0    128.6 (887)  127.7 (880)                                                                             0.7                                       30.0/70.0    126.2 (870)  124.0 (855)                                                                             1.7                                       40.0/60.0    122.8 (847)  119.0 (820)                                                                             3.1                                       50.0/50.0    118.3 (816)  112.9 (778)                                                                             4.6                                       60.0/40.0    112.6 (776)  106.0 (731)                                                                             5.9                                       70.0/30.0    105.5 (727)   98.6 (680)                                                                             6.5                                       80.0/20.0     97.0 (669)   90.9 (627)                                                                             6.3                                       90.0/10.0     87.2 (601)   83.4 (575)                                                                             4.4                                       99.0/1.0      77.3 (533)   76.8 (530)                                                                             0.6                                       HFC-134/HFC-263fb                                                             31.0/69.0     81.2 (560)   73.4 (506)                                                                             9.6                                       50.0/50.0     86.0 (593)   84.5 (583)                                                                             1.7                                       67.2/32.8     87.3 (602)   87.3 (602)                                                                             0                                         90.0/10.0     83.3 (574)   81.0 (558)                                                                             2.8                                       99.0/90.0     77.1 (532)   76.5 (527)                                                                             0.8                                       HFC-134/HFC-272ca                                                             51.0/49.0     75.6 (521)   68.4 (472)                                                                             9.5                                       70.0/30.0     79.2 (546)   78.0 (538)                                                                             1.5                                       84.0/16.0     80.3 (554)   80.3 (554)                                                                             0                                         99.0/1.0      76.8 (530)   76.5 (527)                                                                             0.4                                       HFC-134/HFC-281ea                                                             48.0/52.0     74.0 (510)   66.7 (460)                                                                             9.9                                       70.0/30.0     80.0 (552)   78.6 (542)                                                                             1.7                                       84.7/15.3     81.6 (563)   81.6 (563)                                                                             0                                         99.0/1.0      77.1 (532)   76.7 (529)                                                                             0.5                                       HFC-134/HFC-281fa                                                             58.0/42.0     68.9 (475)   62.2 (429)                                                                             9.7                                       80.0/20.0     75.1 (518)   74.0 (510)                                                                             1.5                                       93.8/6.2      76.9 (530)   76.9 (530)                                                                             0                                         99.0/1.0      76.4 (527)   76.3 (526)                                                                             0.1                                       ______________________________________                                    

The results of this Example show that these compositions are azeotropicor azeotrope-like because when 50 wt % of an original composition isremoved, the vapor pressure of the remaining composition is within about10% of the vapor pressure of the original composition, at a temperatureof 25'C.

EXAMPLE 3 Leak Test at 43.9'C.

A leak test is performed as in Example 2, except that the composition isallowed to leak at 43.9'C. The data below show that when 50 wt % of anoriginal composition is removed, the vapor pressure of the remainingcomposition is within about 10% of the vapor pressure of the originalcomposition, at a temperature of 43.9'C.

    ______________________________________                                        HFC-134/cyclopropane                                                          ______________________________________                                        53.5/46.5     199.7 (1377)                                                                             199.7 (1377)                                                                            0.0                                        70.0/30.0     196.6 (1356)                                                                             193.2 (1332)                                                                            1.7                                        89.0/11.0     174.8 (1205)                                                                             157.4 (1085)                                                                            10.0                                       90.0/10.0     172.4 (1189)                                                                             154.7 (1067)                                                                            10.3                                       20.0/80.0     190.3 (1312)                                                                             181.0 (1248)                                                                            4.9                                        10.0/90.0     182.0 (1255)                                                                             173.1 (1193)                                                                            4.9                                         1.0/99.0     170.2 (1173)                                                                             168.8 (1164)                                                                            0.8                                        ______________________________________                                    

EXAMPLE 4 Refrigerant Performance

The following table shows the performance of the inventive refrigerants.The data are based on the following conditions.

    ______________________________________                                        Evaporator temperature                                                                             45.0' F. (7.2' C.)                                       Condenser temperature                                                                             130.0' F. (54.4' C.)                                      Subcool temperature  15.0' F. (8.3' C.)                                       Return gas temperature                                                                             65.0' F. (18.3' C.)                                      ______________________________________                                    

Compressor effciency is 75%.

The refrigeration capacity is based on a compressor with a fixeddisplacement of 3.5 cubic feet per minute and 75% volumetric efficiency.Capacity is intended to mean the change in enthalpy of the refrigerantin the evaporator per pound of refrigerant circulated, i.e. the heatremoved by the refrigerant in the evaporator per time. Coefficient ofperformance (COP) is intended to mean the ratio of the capacity tocompressor work. It is a measure of refrigerant energy efficiency.

    __________________________________________________________________________               Evap. Cond.           Capacity                                     Refrig.    Press.                                                                              Press.                                                                              Comp. Dis.                                                                              BTU/min                                      Comp.      Psia (kPa)                                                                          Psia (kPa)                                                                          Temp. `F. (`C.)                                                                      COP                                                                              (kw)                                         __________________________________________________________________________    HCFC-22    90.6 (625)                                                                          312.6 (2155)                                                                        212.8 (100.4)                                                                        3.41                                                                             351.3 (6.2)                                  HFC-134/HFC-227ca                                                              1.0/99.0  36.8 (254)                                                                          144.2 (994)                                                                         143.0 (61.7)                                                                         3.21                                                                             136.2 (2.4)                                  99.0/1.0   42.2 (291)                                                                          169.9 (1171)                                                                        182.0 (83.3)                                                                         3.59                                                                             188.7 (3.3)                                  HFC-134/HFC-245cb                                                              1.0/99.0  36.5 (252)                                                                          138.5 (955)                                                                         139.3 (59.6)                                                                         3.31                                                                             137.6 (2.4)                                  99.0/1.0   42.3 (292)                                                                          170.2 (1173)                                                                        182.0 (83.3)                                                                         3.58                                                                             188.9 (3.3)                                  HFC-134/(CF.sub.3).sub.3 N                                                     5.0/95.0  29.3 (202)                                                                          125.9 (868)                                                                         135.5 (57.5)                                                                         3.17                                                                             113.0 (2.0)                                  95.0/5.0   43.6 (301)                                                                          174.0 (1200)                                                                        179.6 (82.0)                                                                         3.59                                                                             193.0 (3.4)                                  HFC-134/SF.sub.5 CF.sub.3                                                      1.0/99.0  46.5 (321)                                                                          195.9 (1351)                                                                        155.5 (68.6)                                                                         3.17                                                                             179.0 (3.2)                                  99.0/1.0   42.6 (294)                                                                          171.1 (1780)                                                                        182.1 (83.4)                                                                         3..60                                                                            190.5 (3.4)                                  HFC-134/cyclopropane                                                           1.0/99.0  62.9 (434)                                                                          217.4 (1499)                                                                        201.1 (93.9)                                                                         3.64                                                                             261.2 (4.6)                                  99.0/1.0   44.5 (307)                                                                          178.6 (1231)                                                                        174.3 (79.1)                                                                         3.61                                                                             199.2 (3.5)                                  HFC-134/C216                                                                   1.0/99.0  58.1 (401)                                                                          195.6 (1349)                                                                        142.0 (61.1)                                                                         3.14                                                                             186.7 (3.3)                                  99.0/1.0   43.0 (296)                                                                          174.5 (1203)                                                                        473.9 (78.8)                                                                         3.58                                                                             192.2 (3.4)                                  HFC-134/HFC-161                                                                 1/99     78.3 (540)                                                                          276.4 (1905)                                                                        202.6 (94.8)                                                                         3.49                                                                             314.4 (5.5)                                    99/1     42.9 (296)                                                                          174.7 (1205)                                                                        175.0 (79.4)                                                                         3.57                                                                             192.1 (3.4)                                  HFC-134/HFC-263fb                                                              5.0/95.0  31.5 (217)                                                                          123.3 (850)                                                                         155.8 (68.8)                                                                         3.54                                                                             133.4 (2.3)                                  99.0/1.0   42.1 (290)                                                                          169.4 (1168)                                                                        182.0 (83.3)                                                                         3.59                                                                             188.5 (3.3)                                  HFC-134/HFC-272ca                                                              5.0/95.0  19.8 (137)                                                                           81.5 (562)                                                                         161.4 (71.9)                                                                         3.71                                                                             93.0 (1.6)                                   99.0/1.0   41.8 (288)                                                                          168.2 (1160)                                                                        182.1 (83.4)                                                                         3.60                                                                             187.3 (3.3)                                  HFC-134/HFC-281ea                                                              5.0/95.0  26.9 (185)                                                                          106.6 (735)                                                                         168.6 (75.9)                                                                         3.69                                                                             122.6 (2.2)                                  99.0/1.0   41.8 (288)                                                                          168.3 (1160)                                                                        182.2 (83.4)                                                                         3.59                                                                             187.3 (3.3)                                  HFC-134/HFC-281fa                                                              5.0/95.0  21.2 (146)                                                                           88.6 (611)                                                                         169.9 (76.6)                                                                         3.73                                                                             101.7 (1.8)                                  99.0/1.0   41.5 (286)                                                                          167.6 (1156)                                                                        182.3 (83.5)                                                                         3.60                                                                             186.6 (3.3)                                  __________________________________________________________________________

EXAMPLE 5

This Example is directed to measurements of the liquid/vapor equilibriumcurves for the mixtures in FIGS. 3 and 6-10.

Turning to FIG. 3, the upper curve represents the composition of theliquid, and the lower curve represents the composition of the vapor.

The data for the compositions of the liquid in FIG. 3 are obtained asfollows. A stainless steel cylinder is evacuated, and a weighed amountof HFC-134 is added to the cylinder. The cylinder is cooled to reducethe vapor pressure of HFC-134, and then a weighed amount of (CF₃)₃ N isadded to the cylinder. The cylinder is agitated to mix the HFC-134 and(CF₃)₃ N, and then the cylinder is placed in a constant temperature bathuntil the temperature comes to equilibrium at 25'C, at which time thevapor pressure of the HFC-134 and (CF₃)₃ N in the cylinder is measured.Additional samples of liquid are measured the same way, and the resultsare plotted in FIG. 3.

The curve which shows the composition of the vapor is calculated usingan ideal gas equation of state.

Vapor/liquid equilibrium data are obtained in the same way for themixtures shown in FIGS. 6-10.

The data in FIGS. 3 and 6-10 show that at 25'C, there are ranges ofcompositions that have vapor pressures higher than the vapor pressuresof the pure components of the composition at that same temperature. Asstated earlier, the higher than expected pressures of these compositionsmay result in an unexpected increase in the refrigeration capacity andefficiency for these compositions verus the pure components of thecompositions.

EXAMPLE 6

This Example is directed to measurements of the liquid/vapor equilibriumcurve for mixtures in FIGS. 1-2 and 4-5. The upper curve represents theliquid composition, and the lower curve represents the vaporcomposition.

The procedure for measuring the composition of the liquid for mixturesof HFC-134 and HFC-227ca in FIG. 1 was as follows. A stainless steelcylinder was evacuated, and a weighed amount of HFC-134 was added to thecylinder. The cylinder was cooled to reduce the vapor pressure ofHFC-134, and then a weighed amount of HFC-227ca was added to thecylinder. The cylinder was agitated to mix the HFC-134 and HFC-227ca,and then the cylinder was placed in a constant temperature bath untilthe temperature came to equilibrium at 11.2'C, at which time the vaporpressure of the content of the cylinder was measured. Samples of theliquid in the cylinder were taken and analyzed, and the results areplotted in FIG. 1 as asterisks, with a best fit curve having been drawnthrough the asterisks.

This procedure was repeated for various mixtures of HFC-134 andHFC-227ca as indicated in FIG. 1.

The curve which shows the composition of the vapor is calculated usingan ideal gas equation of state.

The data in FIG. 1 show that at 11.2'C, there are ranges of compositionsthat have vapor pressures higher than the vapor pressures of the purecomponents of the composition at that same temperature. As statedpreviously, the higher than expected pressures of these compositions mayresult in an unexpected increase in the refrigeration capacity andefficiency for these compositions versus the pure components of thecompositions.

The same procedure was used for measuring the vapor pressure of themixtures shown in FIGS. 2 and 4-5, except that the measurements of thevapor pressure of mixtures of FIG. 4 were taken at 14.4'C and themeasurements of the vapor pressure of mixtures of FIG. 5 were taken at43.9'C.

The novel compositions of this invention, including the azeotropic orazeotrope-like compositions, may be used to produce refrigeration bycondensing the compositions and thereafter evaporating the condensate inthe vicinity of a body to be cooled. The novel compositions may also beused to produce heat by condensing the refrigerant in the vicinity ofthe body to be heated and thereafter evaporating the refrigerant.

The compositions of the present inventions are useful as blowing agentsin the production of thermoset foams, which include polyurethane andphenolic foams, and thermoplastic foams, which include polystyrene orpolyolefin foams.

A polyurethane foam may be made by combining a composition of thepresent invention, which functions as a blowing agent, together with anisocyanate, a polyol, and appropriate catalysts or surfactants to form apoylurethane or polyisocyanurate reaction formulation. Water may beadded to the formulation raction to modify the foam polymer as well asto generate carbon dioxide as an in-situ blowing agent.

A phenolic foam may be produced by combining a phenolic resin or resole,acid catalysts, a blowing agent of the present invention and appropriatesurfactants to form a phenolic reaction formulation. The formulation maybe chosen such that either an open cell or closed cell phenolic foam isproduced.

Polystyrene or polyolefin foams may be made by extruing a molten mixureof a polymer, such as polystyrere, polyethylene or polypropylene), anucleating agent and a blowing agent of the present invention through anextrusion die that yields the desired foam product profile.

The novel compositions of this invention, including the azeotropic orazeotrope-like compositions, may be used as cleaning agents to clean,for example, electronic circuit boards. Electronic components aresoldered to circuit boards by coating the entire circuit side of theboard with flux and thereafter passing the flux-coated board overpreheaters and through molten solder. The flux cleans the conductivemetal parts and promotes solder fusion, but leave residues on thecircuit boards that must be removed with a cleaning agent. This isconventionally done by suspending a circuit board to be cleaned in aboiling sump which contains the azeotropic or azeotrope-likecomposition, then suspending the circuit board in a rinse sump, whichcontains the same azeotropic or azeotrope-like composition, and finally,for one minute in the solvent vapor above the boiling sump.

As a further example, the azeotropic mixtures of this invention can beused in cleaning processes such as described in U.S. Pat. No. 3,881,949,or as a buffing abrasive detergent.

It is desirable that the cleaning agents be azeotropic or azeotrope-likeso that they do not tend to fractionate upon boiling or evaporation.This behavior is desirable because if the cleaning agent were notazeotropic or azeotrope-like, the more volatile components of thecleaning agent would preferentially evaporate, and would result in acleaning agent with a changed composition that may become flammable andthat may have less-desirable solvency properties, such as lower rosinflux solvency and lower inertness toward the electrical components beingcleaned. The azeotropic character is also desirable in vapor degreasingoperations because the cleaning agent is generally redistilled andemployed for final rinse cleaning.

The novel compositions of this invention are also useful as fireextinguishing agents, heat transfer media, gaseous dielectrics, andpower cycle working fluids.

ADDITIONAL COMPOUNDS

Other components, such as aliphatic hydrocarbons having a boiling pointof -60 to +60'C, hydrofluorocarbonalkanes having a boiling point of -60to +60'C, hydrofluoropropanes having a boiling point of between -60 to+60'C, hydrocarbon esters having a boiling point between -60 to +60'C,hydrochlorofluorocarbons having a boiling point between -60 to +60'C,hydrofluorocarbons having a boiling point of -60 to +60'C,hydrochlorocarbons having a boiling point between -60 to +60'C,chlorocarbons and perfluorinated compounds, can be added to theazeotropic or azeotrope-like compositions described above.

Additives such as lubricants, corrosion inhibitors, surfactants,stabilizers, dyes and other appropriate materials may be added to thenovel compositions of the invention for a variety of purposes providesthey do not have an adverse influence on the composition for itsintended application. Preferred lubricants include esters having amolecular weight greater than 250.

We claim:
 1. An azeotropic or azeotrope-like composition consistingessentially of 1-99 weight percent 1,1,2,2-tetrafluoroethane and 1-99weight percent of fluoroethane, wherein the vapor pressure of saidcomposition at 25° C. is about 77.3 to about 130.3 psia.
 2. A processfor producing refrigeration, comprising condensing a composition ofclaim 1 and thereafter evaporating said composition in the vicinity ofthe body to be cooled.
 3. A process for producing heat comprisingcondensing a composition of claim 1 in the vicinity of a body to beheated, and thereafter evaporating said composition.
 4. A process forcleaning a solid surface comprising treating said surface with acomposition of claim
 1. 5. A process of preparing a thermoset orthermoplastic foam comprising the step of foaming a mixture of thecomposition of claim 1 and a thermoset or thermoplastic material.